Year	Percent
1990	75.566
1991	76.105
1992	76.611
1993	77.052
1994	77.534
1995	78.015
1996	78.286
1997	78.551
1998	78.797
1999	79.048
2000	78.816
2001	78.579
2002	78.332
2003	78.076
2004	77.815
2005	77.554
2006	77.303
2007	77.05
2008	76.797
2009	76.544
2010	76.294
2011	76.048
2012	75.804
2013	75.56
2014	75.862
2015	76.098
2016	76.221
2017	76.044
2018	75.865
2019	75.686
2020	75.504
2021	75.321
2022	75.135
2023	74.948
2024	74.759
2025	74.567
2026	74.373
2027	74.175
2028	73.973
2029	73.769
2030	73.565